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Biotechnology
Biotechnology is a field of biology which exploits biological processes for industrial (the production of antibiotics, hormones, etc.) and other purposes. History Background Biotechnology has been employed by humans since the beginning of agriculture, including the selective breeding of corn (which originated from the teosinte grass, which crossed with other grasses to create corn), the start of agriculture and plant-breeding during the Neolithic period, and the domestication and selective breeding of animals. All modern breeds of dogs originate from the domestication of the grey wolf; dogs and the grey wolf are so similar that they are members of the same species (dogs and grey wolves can have viable, fertile offspring). Selective dog breeding was one of the examples used by Charles Darwin to validate his ideas of natural selection as the method of creating evolutionary changes originating from a common ancestor. There are now more than 200 common dog breeds, used to fulfill many different purposes, from hunting to being lap dogs. Today, it is also known that neanderthals and humans are the same species, interbreeding and creating homo sapiens. Modern biotechnology Modern biotechnology can be thought of starting with the understanding that nucleic acids are the genetic material, of the molecular structure of the DNA molecule, that nucleic acids are the universal genetic material on Earth, and that within the molecule is the genetic code to direct the cell's metabolism as well as the base pairing that facilitates replication of this genetic material (and the molecular information stored within it) to successive generations of cells. Humans manipulate biotechnology for drug discovery and drug manufacture, genetic engineering, cloning DNA, recombinant DNA technologies, nuclear transplantation (cloning), designer proteins, monoclonal antibodies, and gene therapy. Wolf-dogs can be created by the mating of a wolf and a dog, sheep-goat chimeras can be created by the fusion of a sheep and goat zygote, and other hybrid and transgenic animals animals can be created through zygote fusion. In addition, glowing rabbits and cats can be created through implanting new genes in animals' DNA. Other important factors in using biotechnolgy include the understanding of the human genome and the molecular level of genetic variation; the development of methodologies to sequence the human genome for less than $1,000 are well underway and could lead to personalized medicine. In addition, haplotype mapping and understanding the epigenome can provide humans with a better understanding of genetic expression. Modern biotechnology and the pharmaceutical industry have already made a profound influence in drug discovery, isolation, and purification by using new techniques. Many genetically-engineered products are available, and monoclonal antibodies, epidermal growth factors, human insulin, interleukins, many cytokines, Factor VIII (a substance used to control hemophiliacs) are some of the techniques used. At Genitech, scientists discovered a means to isolate human insulin and put it into bacteria, allowing for the bacteria to express the human insulin gene and produce protein. Recombinant DNA technologies insert desired genes into suitable vectors, which get inserted into the genomes of cells in culture. The tissue culture cells that contain the inserts are selected, and they produce the desired gene products which can be harvested and purified, resulting in biologically-active products. Other fields of biotechnology include microbial (use of prokaryotic organisms), agricultural (from plant resistance to better rice, wheat, corn, etc.), animal (creation of bioreactors), forensic DNA fingerprinting (identity), bioremediation (genetically-engineered microbes), aquatic (genetically-modifying fish, as well as fish-farming), and medical (preventative medicine, regenerative medicine, better cures and treatments, stem cell therapies, gene therapy, and reproductive technologies). During the 21st century, a true scientific revolution occurred, turning biology from a descriptive science to a synthetic science. There are now tools which can investigate the common genetic diseases as well as to learn more about the gene interaction of single-gene diseases, genetic risks, and so on. These innovations provide more employment opportunities such as research and development jobs, and principal investors include manufacturing and production, quality assurance, quality control, government oversight, and startup biotech firms. As of 2019, the burgeoning biotechnology industry makes $13 billion a year. As a science matures, it goes through different steps, moving fromt he sphere of analysis to that of synthesis. This occurred in the field of genetics, leading to the new field of biotechnology. Beginnings of Recombinant DNA Technology During the 1970s, DNA cloning techniques developed, transforming genetic research - it opened up the possibility of studying entire genomes (genomics), of manipulating genes, of moving genes from one species to another species (recombinant genetics), and revolutionary possibilities for medicine, agriculture, ecology, forensics, and other scientific fields. Major steps in the development of biotechnology from 1970 to 2000 include the use of enzymes to cut up and reassemble DNA into smaller pieces, cloning these fragments into large amounts to facilitate studies (DNA cloning), sequencing the DNA fragments to know the exact genetic letters in the fragments, and decoding the fragments and putting them together to determine actual gene sequences (the Human Genome Project of the 1990s to 2003). DNA cloning was vital to innovations in gene editing and other forms of biotechnology. A cloning vector and eukaryotic chromosomes were separately cleaved with the same restriction endonuclease; the fragments were then cloned and ligated to the cloning vector. The resulting recombinant DNA was then introduced into a host cell where it could be propagated (cloned). This formed the basis of genetic engineering during the 1970s; Stanford professor Paul Berg and 1980 Nobel Prize recipient was the brilliant mind behind this scientific revolution. Hamilton O. Smith was the first to isolate Type II restriction enzymes, cleaving at specific sites. Type II was easier to use for genetic engineering, as it did not require ATP; it could give "blunt" or "sticky ends" which were most useful for manipulation. He came up with different types of scissors to cut the DNA, recognizing different base pairs. The five-pair fragments are easier to cut than the nine-pair fragments. Endonucleases are the tools which can cut the DNA fragments; the size of the fragment is related to the size of the recognition site, and, to some extent, the species of DNA being cut. There are more bases in the recognition site. DNA ligase can be used to link the fragments, although joining is much less efficient with blunt ends than sticky ends. The ligase is used to create covalent bonds between the fragments and cuts made by the same restriction enzyme in the cloning vector. The artificial plasmas, polylinkers, are synthetic nucleotide sequences that can be placed into a plasmid, having a site for specific endonuclease, and serving as an excellent research tool. Berg was the first to use all the different tools to insert a DNA molecule from one species into another species, raising the awareness of the many possibilities of recombinant DNA technology. Both scientsits and government administrators thought about regulatory policies when experimenting with recombinant DNA, as they feared that Berg's discovery would allow fro humans to create new bacteria or viruses. At Monterey in California, he called a conference to receive the advice of other scientists as to how to control the new industry. At the Asilomar Conference on Recombinant DNA in February 1975, 140 professional scientists (primarily biologists, but also lawyers and physicians) participated in the conference to draw up voluntary guidelines to ensure the safety of recombinant DNA technology. The conference also placed scientific research more into the public domain, and could be seen as applying a version of the precautionary principle. The conference advised that the government should be involved with the research in order to regulate it. At the same time, Berg, Herbert Boyer, and Stanley N. Cohen went to a deli in San Francisco and talked about their research on the capabilities of restriction enzymes, and Cohen and Boyer decided to collaborate, forming the beginning of the first biotech company. Boyer later worked with Robert A. Swanson to form a biotechnology company, Genitech, in 1976; it was the first biotechnology company ever produced, and its first product was somatostatin (1977), a growth hormone. It was the first product made by a bacteria that produced a human hormone that could be sold; their creation of synthetic human insulin in 1978 was a huge money-maker for the company. Roche later merged with Genitech to form the Roche Group, one of the largest mergers of two companies in history. The next important step was the placing of fragments of DNA in viruses. Scientists could create viruses with normal genes, using them for treatment of people born with defective genes. The construction of viruses with necessary gene sequences and their usage to infect cells was another important part of the innovations in genetic engineering. The next step was the sequencing of the fragments, pioneered by Berg, Walter Gilbert, and Frederick Sanger. One half of the 1980 Nobel Prize in Chemistry was awarded to Paul Berg, while Gilbert and Sanger shared the other half for their contributions concerning the determination of base sequences in nucleic acids. Berg cut amino acids off of proteins one-at-a-time before analyzing them; for DNA, he attempted to do the same thing with nucleotides. However, this method did not work, as the molecules were too big. Instead, he decided to use the strand that it copied. Instead of cutting off the pieces, he added one each time, marking it as one that was made. Using reverse thinking, he matched the nucleotide pieces when he made them, and, over the next several decades, the process was automated and made more quick. Sanger came up with a method to read DNA fragments, using DNA polymerase, deoxy-nucleotides, and primers to create a reaction mixture. Sanger created DNA sequences of different lengths, with the largest chains remaining at the top of the "sieve" of gel involved in the process. This process was also automated, with the DNA sequence being read by determining the sequence of colors in the peaks as they passed through a detector; this information was fed directly to a computer, which determined the sequence. During the 1980s, chemical amplification was developed through a polymerase chain reaction. Nobel Prize-winning technology, it became the basis of numerous tests that spanned genetic disease diagnosis to identification of infectious organisms to forensics to identity testing to anthropology and more; it has become an incredibly important technique, and was used in several forensics cases. Kary Mullis won the Nobel Prize for his work on the process while serving as a technologist. PCR can be used for DNA testing, personal DNA stories, and other uses. Later, Francis S. Collins and J. Craig Venter pioneered genomic sequencing, initiating the Human Genome Project in 1989 and working on the genomes of bacterium, budding yeast, nematode worms, fruit flies, plants, humans, fission yeasts, mice, rice, chimpanzees, protists, sea urchins, and honeybees. Genes were isolated from a genomic library, were ordered into a detailed physical map, and were sequenced by shotgun sequencing protocols. In 2010, after improvements in sequencing techniques, the entire genome of neanderthals was reported. This led to important insights into who our common ancestor was (homo erectus), and when the spliit occurred that gave rise to homo sapiens and the neanderthals some 370,000 years ago. The human genome project completed the DNA sequence of 3.2 billion bp of human DNA in 2003, as well as 22,000 genes; they had full coverage of the genome with genetic markers in the HAPMAP project. There are 5,000 known single-gene diseases (Cystic fibrosis, tay-sachs, etc.), caused by mutations in a single gene and only in tha tgene. Genetic testing for common mutation in the gene can be a problem if ethnic population differences exist; the solution is whole gene Next Generatio DNA sequencing. Multifactorial diseases such as cancer, diabetes, obesity, and Alzheimer's are very common. Mutations of many genes were involved, and they presdisposed but didn't guarantee disease. Contributions of environmental influences are significant. Large multiple gene DNA sequencing panels or whole exome DNA sequencing would be necessary to cure these diseases. The goals in multifactorial human disease include identifying all the genes that significantly contribute to disease (genome-wide DNA microarrays), identifying predisposing mutations of these genes common in the population, and gene sequencing, gene panel, whole exome and whole genome sequencing for individual patients to assess genetic risk for common diseases. Category:Genetics Category:Biology